July 16, 2013
by Shaun Mason

(Medical Xpress)—Researchers from UCLA's Jonsson Comprehensive Cancer Center have discovered that specific types of bacteria that live in the gut are major contributors to lymphoma, a cancer of the white blood cells.

Published online ahead of press today in the journal Cancer Research, the study was led by Robert Schiestl, member of the Jonsson Cancer Center and professor of pathology and laboratory medicine, environmental health sciences, and radiation oncology.

In rodents, intestinal bacteria influence obesity, intestinal inflammation and certain types of epithelial cancers. (Epithelial cancers affect the coverings of the stomach, liver or colon.) However, little is known about the identity of the bacterial species that promote the growth of, or protect the body from, cancer—or about their effect on lymphoma.

Up to 1,000 different species of bacteria (intestinal microbiota) live in the human gut. Intestinal microbiota number 100 trillion cells; over 90 percent of the cells in the body are bacteria. The composition of each person's microbiome—the body's bacterial make-up—is very different, due to the types of bacteria people ingest early in their lives, as well as the effects of diet and lifestyle.

Schiestl's group wanted to determine whether differences in peoples' microbiomes affect their risk for lymphoma, and whether changing the bacteria can reduce this risk. They studied mice with ataxia-telangiectasia (A-T), a genetic disease that in humans and mice is associated with a high rate of B-cell lymphoma. They discovered that, of mice with A-T, those with certain microbial species lived much longer than those with other bacteria before developing lymphoma, and had less of the gene damage (genotoxicity) that causes lymphoma.

"This study is the first to show a relationship between intestinal microbiota and the onset of lymphoma," Schiestl said. "Given that intestinal microbiota is a potentially modifiable trait, these results hold considerable promise for intervention of B-cell lymphoma and other diseases."

The scientists also were able to create a detailed catalog of bacteria types with promoting or protective effects on genotoxicity and lymphoma, which could be used in the future to create combined therapies that kill the bacteria that promote cancer (as antibiotics do) and increase the presence of the bacteria that protect from cancer (as probiotics do).

Related Stories

Researchers at the Sahlgrenska Academy at the University of Gothenburg, Sweden, have discovered a previously unknown mechanism which helps intestinal bacteria to affect the formation of blood vessels. The results, which are ...

Instability in the composition of gut bacterial communities (dysbiosis) has been linked to common human intestinal disorders, including inflammatory bowel disease and colorectal cancer; however, it is unclear if dysbiosis ...

Too much antibiotic can decimate the normal intestinal microbiota, which may never recover its former diversity. That, in turn, renders the GI tract vulnerable to being colonized by pathogens. Now researchers from Memorial ...

Mice with different naturally occurring stomach bacteria have distinct susceptibilities to disease caused by Helicobacter pylori, the well-known cause of ulcers in humans, according to a study published online ahead of print ...

Humans and their pet dogs are close, so close that they both develop a type of cancer called diffuse large B-cell lymphoma. In humans it's the most common lymphoma subtype while in dogs, it's one of the most common cancers ...

Recommended for you

Researchers have identified a new mechanism that the tumor suppressor protein p53 uses to trigger cell death via apoptosis and have shown how the process could be harnessed to kill cancer cells. St. Jude Children's Research ...

Strange rings of DNA that exist outside chromosomes are distinct to the cell types that mistakenly produced them, researchers have discovered. The finding raises the tantalizing possibility that the rings could be used as ...

Resveratrol, a chemical found in red grapes, is more effective in smaller doses at preventing bowel cancer in mice than high doses, according to new research published today in the journal Science Translational Medicine.

In industrialized countries like in Europe, acute lymphoblastic leukemia is the most common form of cancer in children. An international research consortium lead by pediatric oncologists from the Universities of Zurich and ...

Use of gene therapy to deliver a protein that suppresses the development of female reproductive organs may improve the survival of patients with ovarian cancer that has recurred after chemotherapy, which happens 70 percent ...

1 comment

This adds to the research that indicates that gram-negative bacteria in the gut can also cause chronic health problems: "An opportunistic pathogen isolated from the gut of an obese human causes obesity in germfree mice" - ISME J. 2013 Apr;7(4):880-4. doi: 10.1038/ismej.2012.153. Epub 2012 Dec 13.

Please sign in to add a comment.
Registration is free, and takes less than a minute.
Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.